Synthesis of new porphyrazines with tertiary or quaternized aminoethyl substituents

Metal-free and metallo-porphyrazines (M = Mg or Co) carrying eight dimethyl aminoethylthia-groups on peripheral positions have been synthesized from th e disodium salt of dithiomaleonitrile and the hydrochloride of dimethylamin oethylchloride. The magnesium derivative (MgPza) was converted into quatern ized product (MgPzq) by reaction with methyl iodide. The metal-free derivat ive was obtained by treatment with trifluoroacetic acid and its reaction wi th cobalt (II) acetate led to the cobalt derivative (CoPza). Aggregation of MgPzq molecules has been observed in aqueous solution by the blue-shift of the Q-band absorption with an accompanying decrease in intensity. The new compounds have been characterized by elemental analysis, IR, NMR and their electronic spectra. (C) 2000 Elsevier Science Ltd. All rights reserved.